Ross E. Petty

EULAR/PReS endorsed consensus criteria for the classification of childhood vasculitides

Background: There has been a lack of appropriate classification criteria for vasculitis in children. Objective: To develop a widely accepted general classification for the vasculitides observed in children and specific and realistic classification criteria for common childhood vasculitides (Henoch-Schönlein purpura (HSP), Kawasaki disease (KD), childhood polyarteritis nodosa (PAN), Wegener’s granulomatosis (WG), and Takayasu arteritis (TA)). Methods: The project was divided into two phases: (1) the Delphi technique was used to gather opinions from a wide spectrum of paediatric rheumatologists and nephrologists; (2) a consensus conference using nominal group technique was held. Ten international experts, all paediatricians, met for the consensus conference. Agreement of at least 80% of the participants was defined as consensus. Results: Consensus was reached to base the general working classification for childhood vasculitides on vessel size. The small vessel disease was further subcategorised into “granulomatous” and “non-granulomatous.” Final criteria were developed to classify a child as HSP, KD, childhood PAN, WG, or TA, with changes introduced based on paediatric experience. Mandatory criteria were suggested for all diseases except WG. Conclusions: It is hoped that the suggested criteria will be widely accepted around the world because of the reliable techniques used and the international and multispecialist composition of the expert group involved.

CHAPTER 9 – CHRONIC ARTHRITIS IN CHILDHOOD

211 Chronic arthritis, the most common chronic rheumatic disease of childhood, is one of the more frequent chronic illnesses of children and an important cause of shortand long-term disability. It is not a single disease, but a group of related, genetically heterogeneous, phenotypically diverse immuno inflammatory disorders affecting joints and other structures, possibly activated by contact with an external antigen or antigens. Since its introduction in 1994, the term Juvenile Idiopathic Arthritis (JIA) has largely supplanted the terms Juvenile Chronic Arthritis (JCA) and Juvenile Rheumatoid Arthritis (JRA). However, it is necessary to understand the older classifications in order to interpret the literature on the subject. The intent of this chapter is to provide a general introduction to JIA. Each subtype of disease is discussed in separate chapters.

Rubella-associated arthritis. I. Comparative study of joint manifestations associated with natural rubella infection and RA 27/3 rubella immunisation.

Joint manifestations observed during the course of a prospective RA 27/3 rubella immunisation trial were compared with those observed during an intercurrent wild rubella epidemic in an outlying community. Among 44 rubella haemagglutination inhibition (HAI) negative females ranging in age from 17 to 33 years who received rubella vaccine, six (13.6%) developed acute polyarticular arthritis within two to four weeks postvaccine and two (4.5%) had continuing or recurrent arthropathy lasting longer than 18 months. In contrast, among 23 females ranging in age from 11 to 39 years undergoing wild rubella infection, 12 (52.2%) developed acute polyarticular arthritis and seven (30.4%) had recurrent arthropathy 18 months postinfection. Among 23 males ranging in age from 13 to 54 years undergoing wild rubella infection, only two (8.7%) developed acute arthritis and both individuals had continuing joint manifestations 18 months postinfection. Wild rubella infection in adult populations is associated with a higher incidence, increased severity, and more prolonged duration of joint manifestations than is seen after RA 27/3 rubella immunisation.

Prognosis in childhood dermatomyositis

The insidious onset of progressive muscle weakness in a child may go unnoticed until fever, rash, or muscle pain prompts the family to seek medical attention. Although the diagnosis of dermatomyositis may be suspected, and muscle biopsy and electromyography are later confirmatory, the single most useful method of assessment is determination of the concentration of the serum muscle enzymes. Prompt treatment with corticosteroids has undoubtedly contributed to the currently improved prognosis. Of the 18 children reported in this study, one died of trauma, and all of the remaining individuals have been maintained in functional independence.

Neonatal dendritic cells

The capacity of lymphoid dendritic cells from human cord blood or adult peripheral blood to support a mixed leukocyte reaction in cord blood and adult T cells has been compared. Cord blood dendritic cells have a limited ability to induce either adult or cord blood T cells to proliferate in response to typical concentration of phytohemagglutinin or concanavalin A. Adult blood dendritic cells, on the other hand, induce equivalent mitogen responses in cord blood and adult blood T cells. This relative deficiency can be overcome by increasing the concentration of mitogen or the numbers of dendritic cells in the culture. Neonatal primary immune responses may, in part, reflect the reduced function of dendritic cells.

The outcomes of juvenile idiopathic arthritis in children managed with contemporary treatments: results from the ReACCh-Out cohort

Objective To describe clinical outcomes of juvenile idiopathic arthritis (JIA) in a prospective inception cohort of children managed with contemporary treatments. Methods Children newly diagnosed with JIA at 16 Canadian paediatric rheumatology centres from 2005 to 2010 were included. Kaplan–Meier survival curves for each JIA category were used to estimate probability of ever attaining an active joint count of 0, inactive disease (no active joints, no extraarticular manifestations and a physician global assessment of disease activity <10 mm), disease remission (inactive disease >12 months after discontinuing treatment) and of receiving specific treatments. Results In a cohort of 1104 children, the probabilities of attaining an active joint count of 0 exceeded 78% within 2 years in all JIA categories. The probability of attaining inactive disease exceeded 70% within 2 years in all categories, except for RF-positive polyarthritis (48%). The probability of discontinuing treatment at least once was 67% within 5 years. The probability of attaining remission within 5 years was 46–57% across JIA categories except for polyarthritis (0% RF-positive, 14% RF-negative). Initial treatment included joint injections and non-steroidal anti-inflammatory drugs for oligoarthritis, disease-modifying antirheumatic drugs (DMARDs) for polyarthritis and systemic corticosteroids for systemic JIA. Conclusions Most children with JIA managed with contemporary treatments attain inactive disease within 2 years of diagnosis and many are able to discontinue treatment. The probability of attaining remission within 5 years of diagnosis is about 50%, except for children with polyarthritis.

Clinical correlates of antinuclear antibodies in juvenile rheumatoid arthritis

The presence of antinuclear antibodies (ANA) was determined by an immunofluorescent technique in 200 children with juvenile rheumatoid arthritis and was compared to that in 80 children with other connective tissue diseases, 164 children with nonconnective tissue diseases, and 90 normal children. The low frequency of positive tests in normal children (3 per cent) and in nonconnective tissue diseases (1 per cent) compared with the high seropositivity in children with systemic lupus erythematosus (100 per cent), polyarteritis (75 per cent), and juvenile rheumatoid arthritis (38.5 per cent) demonstrates that the method used to detect ANA is both sensitive and selective. In juvenile rheumatoid arthritis, ANA were found significantly more frequently in girls, in patients with early onset of disease or whose present age was young, and in those with polyarticular disease or with monarticular disease and iridocyclitis.

Early outcomes and improvement of patients with juvenile idiopathic arthritis enrolled in a Canadian multicenter inception cohort

To determine early outcomes and early improvements in a prospective inception cohort of children with juvenile idiopathic arthritis (JIA) treated with current standard therapies.

A syndrome of childhood polyarteritis

In this report the clinical, laboratory, and histopathologic findings of nine children with polyarteritis are reviewed. All have had evidence of systemic involvement. Eight presented with fever, calf pain, erythematous painful nodules, and elevation of the acute-phase reactants. All were treated with prednisone at a dosage of 2 mg/kg/day. All of the children are alive but have had relapses at least once during the course of tapering the dosage of corticosteroids. Serious complications of disease have included myocardial infarction, hypertension, and impaired renal function.

The pulmonary manifestations of childhood onset systemic lupus erythematosus

Pleuropulmonary disease in childhood onset SLE is common. It may be insidious or present as a life threatening event. North American Indian children in our population appear to be at high risk for severe lung disease. Pulmonary symptoms are present in the majority of children at some time during their disease course and pulmonary function studies are abnormal in the majority of patients. The pulmonary manifestations and frequency of occurrence in childhood appear to be similar to that described in adult onset SLE. Although pulmonary function studies do not correlate well with pulmonary symptoms, these studies provide objective quantification of the type and severity of the functional lesion. Serial tests may be helpful in monitoring disease activity in childhood SLE.